Messages in this thread | | | Date | Wed, 11 Mar 2020 10:04:47 +0100 | From | Joerg Roedel <> | Subject | Re: [PATCH] x86/ioremap: Map EFI runtime services data as encrypted for SEV |
| |
Hi,
On Tue, Mar 10, 2020 at 06:47:31PM +0100, Borislav Petkov wrote: > Ok, here's what I have. @joro, I know it is trivially different from the > version you tested but I'd appreciate it if you ran it again, just to be > sure.
Looks good and ested it, works fine.
Reviewed-by: Joerg Roedel <jroedel@suse.de> Tested-by: Joerg Roedel <jroedel@suse.de>
> --- > >From 244b62ca142c6296361bde953488fc64db31f1bd Mon Sep 17 00:00:00 2001 > From: Tom Lendacky <thomas.lendacky@amd.com> > Date: Tue, 10 Mar 2020 18:35:57 +0100 > Subject: [PATCH] x86/ioremap: Map EFI runtime services data as encrypted for > SEV > > The dmidecode program fails to properly decode the SMBIOS data supplied > by OVMF/UEFI when running in an SEV guest. The SMBIOS area, under SEV, is > encrypted and resides in reserved memory that is marked as EFI runtime > services data. > > As a result, when memremap() is attempted for the SMBIOS data, it > can't be mapped as regular RAM (through try_ram_remap()) and, since > the address isn't part of the iomem resources list, it isn't mapped > encrypted through the fallback ioremap(). > > Add a new __ioremap_check_other() to deal with memory types like > EFI_RUNTIME_SERVICES_DATA which are not covered by the resource ranges. > > This allows any runtime services data, which has been created encrypted, > to be mapped encrypted. > > [ bp: Move functionality to a separate function. ] > > Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> > Signed-off-by: Borislav Petkov <bp@suse.de> > Cc: <stable@vger.kernel.org> # 5.3 > Link: https://lkml.kernel.org/r/2d9e16eb5b53dc82665c95c6764b7407719df7a0.1582645327.git.thomas.lendacky@amd.com > --- > arch/x86/mm/ioremap.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c > index 44e4beb4239f..935a91e1fd77 100644 > --- a/arch/x86/mm/ioremap.c > +++ b/arch/x86/mm/ioremap.c > @@ -106,6 +106,19 @@ static unsigned int __ioremap_check_encrypted(struct resource *res) > return 0; > } > > +/* > + * The EFI runtime services data area is not covered by walk_mem_res(), but must > + * be mapped encrypted when SEV is active. > + */ > +static void __ioremap_check_other(resource_size_t addr, struct ioremap_desc *desc) > +{ > + if (!sev_active()) > + return; > + > + if (efi_mem_type(addr) == EFI_RUNTIME_SERVICES_DATA) > + desc->flags |= IORES_MAP_ENCRYPTED; > +} > + > static int __ioremap_collect_map_flags(struct resource *res, void *arg) > { > struct ioremap_desc *desc = arg; > @@ -124,6 +137,9 @@ static int __ioremap_collect_map_flags(struct resource *res, void *arg) > * To avoid multiple resource walks, this function walks resources marked as > * IORESOURCE_MEM and IORESOURCE_BUSY and looking for system RAM and/or a > * resource described not as IORES_DESC_NONE (e.g. IORES_DESC_ACPI_TABLES). > + * > + * After that, deal with misc other ranges in __ioremap_check_other() which do > + * not fall into the above category. > */ > static void __ioremap_check_mem(resource_size_t addr, unsigned long size, > struct ioremap_desc *desc) > @@ -135,6 +151,8 @@ static void __ioremap_check_mem(resource_size_t addr, unsigned long size, > memset(desc, 0, sizeof(struct ioremap_desc)); > > walk_mem_res(start, end, desc, __ioremap_collect_map_flags); > + > + __ioremap_check_other(addr, desc); > } > > /* > -- > 2.21.0 > > -- > Regards/Gruss, > Boris. > > https://people.kernel.org/tglx/notes-about-netiquette
| |